Ceasefire takes effect in Syria

A ceasefire brokered by the United States and Russia took effect on Monday as the sun went down across Syria.

The ceasefire the second attempt this year byWashington and Moscow to halt the five-year civil war came into effect at 7 p.m. local time,albeit withmixed messages of commitment from the various rebel factions seeking to topple the government ofPresident Bashar al-Assad.

The Syrian army confirmed a seven-day "calm" would be applied across the war-torn country, but said it reservedthe right to respond decisively "to any violation by the armed groups."

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Assad made a rare public appearance earlier in the dayby attending prayers for the Muslim holiday of Eid al-Adha at a mosque in the Damascus suburb of Daraya.The suburb, previously held by the rebels, surrendered last month and reverted to Damascus's control after four years of government siege.

He saidhis government is determined to "reclaim every area from the terrorists, and to rebuild" the country.

"We call on all Syrians to turn toward reconciliation," he said in an interview with the state news agency SANA.

The ceasefire deal, hammered out between U.S. Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov in Geneva on Saturday, allows the Syrian government to continue to strike at the Islamic State in Iraq and Syria (ISIS)and al-Qaeda-linked militants with the Jabhat Fatah al-Sham group, earlier known as the Nusra Front, until the U.S. and Russia take over the task in one week's time.

Some airstrikes possible

Later Monday,Kerryraisedthe possibility of the U.S. and Russia approving airstrikes byAssad's government as part of a new ceasefire agreement.

Kerry says Syria's government is not supposed to bomb the opposition under the truce that went into effect Monday.

But Kerry says Assad will be able to go after the Nusra Front in certain areas.

After seven days of calm, the U.S. and Russia would then co-operate on how to combat Nusra.

But Kerry said Monday that Assad would still be allowed to target Nusra after that point if strikes "are agreed upon with Russia and the United States."

The U.S. had not previously spoken about approving Syrian government attacks.

Kerry also said early reportssuggested there had been some reduction in violence.

He told reporters at the State Department that it was tooearly to draw a definitive conclusion about how effective the
truce will be, and that there would no doubt be some reports of violations "here and there."

Deep reservations

Rebel factions have expressed deep reservations about the deal.

Under the terms of the agreement, the rebels and the Syrian government are expected to stop attacking one another. Along with Assad's government, his key allies Russia, Iran and the Lebanese militant group Hezbollah have also endorsed the deal.

But that scenario is complicated by the fact that Jabhat Fatah al-Sham remains intertwined with several other groups fighting on the ground.

One of the more immediate goals of the Kerry-Lavrov agreement is to allow the UN to establish aid corridors into Aleppo, the contested northern Syrian city. Over 2,000 people have been killed in fighting over the past 40 days in the city, including 700 civilians and 160 children, according to a Syrian human rights group.

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On Saturday, presumed Russian or government airstrikes on rebel-held Idlib and Aleppo provinces killed over 90 civilians, including 13 children in an attack on a marketplace in Idlib, according to the Britain-based Syrian Observatory for Human Rights.

In the aftermath, rebels and opposition activists were asking on Sunday whether the government's side could be trusted.

Several previous negotiated ceasefires have all eventually collapsed. A partial "cessation of hostilities" that brought sorely needed relief to civilians in March unraveled as the government continued to strike targets in opposition areas, including near a hospital and school near Damascus and a marketplace in Idlib province, killing dozens of civilians.

Previous ceasefires were also preceded by soaring violence as parties on all sides sought to improve their positions in the build-up.

No-fly zone

In Turkey, meanwhile, President Recep Tayyip Erdogan reiterated his earlier calls for establishing a no-fly zone in northern Syria, saying it is essential to boosting security in the area.

Erdogan said he told the leaders of Germany, France, Russia and the U.S. that training and equipping troops on the ground to battle back Islamic State group forces is "not enough" and that a no-fly zone should be the next step.

Speaking after holiday prayers on Monday, Erdogan said Turkey remains resolute in eliminating the threat posed by the Islamic State group at its borders and has made that clear to world leaders.

Turkey launched an incursion into northern Syria in late August, driving ISIS away from the border and also seeking to counter the advance of U.S.-backed Kurdish forces, which Ankara views with suspicion.

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